U.S. Pat. No. 4,045,988, which is assigned to the assignee of the present invention, discloses a rotary forming machine wherein a pair of spaced tool spindles mount rotary die racks having partially circular forming faces for forming a workpiece mounted on a workpiece spindle between the tool spindles. During driving rotation of the tool spindles, the forming faces on cooperable pairs of the die racks engage the workpiece in a 180.degree. opposed relationship to provide forming of teeth or splines in the workpiece by a rolling operation. Each die rack has a mounting surface that faces in the opposite direction as the forming face engaged with a tool spindle support surface which is oriented in a radial direction with respect to the axis of the associated tool spindle rotation.
Precise forming of workpieces with the rotary machine described above requires that the forming face of each die rack on the tool spindles be accurately located with respect to the mounting surface thereof which is engaged with the tool spindle. Also, it is of course necessary to manufacture the die racks with the accurately located forming faces and mounting surfaces as economically as possible in order to minimize the cost of the resultant formed pieces made by the machine.